input.go

// Copyright 2015-2023 Bleemeo
//
// bleemeo.com an infrastructure monitoring solution in the Cloud
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package internal

import (
	"github.com/bleemeo/glouton/inputs"
	"github.com/bleemeo/glouton/logger"

	"github.com/influxdata/telegraf"
	"github.com/influxdata/telegraf/models"
)

// Input is a generic input that use the modifying Accumulator defined in this package.
type Input struct {
	telegraf.Input
	Accumulator Accumulator
	Name        string

	startError error
	logger     *logger.TelegrafLogger
}

// Gather takes in an accumulator and adds the metrics that the Input
// gathers. This is called every "interval".
func (i *Input) Gather(acc telegraf.Accumulator) error {
	i.Accumulator.Accumulator = acc
	i.Accumulator.PrepareGather()

	err := i.Input.Gather(&i.Accumulator)
	if err != nil {
		// Use the telegraf logger which limits log spamming.
		i.logger.Error(err)

		return err
	}

	return nil
}

// Start the ServiceInput.  The Accumulator may be retained and used until
// Stop returns.
func (i *Input) Start(acc telegraf.Accumulator) error {
	i.Accumulator.Accumulator = acc
	if si, ok := i.Input.(telegraf.ServiceInput); ok {
		i.startError = si.Start(&i.Accumulator)

		return i.startError
	}

	return nil
}

// Init performs one time setup of the plugin and returns an error if the
// configuration is invalid.
func (i *Input) Init() error {
	i.fixTelegrafInput()

	if si, ok := i.Input.(telegraf.Initializer); ok {
		return si.Init()
	}

	return nil
}

// Stop stops the services and closes any necessary channels and connections.
func (i *Input) Stop() {
	if si, ok := i.Input.(telegraf.ServiceInput); ok {
		// Stop the service only if it started properly to avoid panic.
		if i.startError == nil {
			si.Stop()
		}
	}
}

// fixTelegrafInput do some fix to make Telegraf input working.
// It try to initialize all fields that must be initialized like Log.
func (i *Input) fixTelegrafInput() {
	i.logger = logger.NewTelegrafLog(i.Name)
	models.SetLoggerOnPlugin(i.Input, i.logger)
}

// SecretCount allows getting the secret count of the underlying input.
func (i *Input) SecretCount() int {
	if si, ok := i.Input.(inputs.SecretfulInput); ok {
		return si.SecretCount()
	}

	return 0
}

// InputWithSecrets wraps an Input that has secrets.
type InputWithSecrets struct {
	*Input
	Count int
}

func (si InputWithSecrets) SecretCount() int {
	return si.Count
}